Red Flags for Low Back Pain Are Not Always Really Red: A Prospective Evaluation of the Clinical Utility of Commonly Used Screening Questions for Low Back Pain
One page on PainSci cites Premkumar 2018: When to Worry About Low Back Pain
PainSci notes on Premkumar 2018:
Premkumar et al present evidence that the traditional “red flags” for ominous causes of back pain can be quite misleading. The correlation between red flags and ominous diagnoses is poor, and prone to producing false negatives: that is, sometimes there are no red flags even when there rally is something more serious going on. In a survey of almost 10,000 patients:
“the absence of red flag responses did not meaningfully decrease the likelihood of a red flag diagnosis.”
This is not even remotely a surprise to anyone who paid attention in back pain school, but it’s good to have some hard data on it.
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
BACKGROUND: Low back pain has a high prevalence and morbidity, and is a source of substantial health-care spending. Numerous published guidelines support the use of so-called red flag questions to screen for serious pathology in patients with low back pain. This paper examines the effectiveness of red flag questions as a screening tool for patients presenting with low back pain to a multidisciplinary academic spine center.
METHODS: We conducted a retrospective review of the cases of 9,940 patients with a chief complaint of low back pain. The patients completed a questionnaire that included several red flag questions during their first physician visit. Diagnostic data for the same clinical episode were collected from medical records and were corroborated with imaging reports. Patients who were diagnosed as having a vertebral fracture, malignancy, infection, or cauda equina syndrome were classified as having a red flag diagnosis.
RESULTS: Specific individual red flags and combinations of red flags were associated with an increased probability of underlying serious spinal pathology, e.g., recent trauma and an age of>50 years were associated with vertebral fracture. The presence or absence of other red flags, such as night pain, was unrelated to any particular diagnosis. For instance, for patients with no recent history of infection and no fever, chills, or sweating, the presence of night pain was a false-positive finding for infection>96% of the time. In general, the absence of red flag responses did not meaningfully decrease the likelihood of a red flag diagnosis; 64% of patients with spinal malignancy had no associated red flags.
CONCLUSIONS: While a positive response to a red flag question may indicate the presence of serious disease, a negative response to 1 or 2 red flag questions does not meaningfully decrease the likelihood of a red flag diagnosis. Clinicians should use caution when utilizing red flag questions as screening tools.
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
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